Headaches are difficult. People who live with headaches can understand how frustrating and disabling they can be. Not only are they painful but they make regular activities of life a struggle to perform and can cause people to miss important family activities. Headaches affect about 50% of the world’s adult population per year, according to the World Health Organization. There are many different types and subtypes of headaches, some even overlapping in classification.
What is the myodural bridge (MDB)?
Anatomical studies have shown, through cadaveric dissection, broad fascial connections between the dura mater and the suboccipital muscles especially the rectus capitis posterior major and minor muscles. This connection is called the myodural bridge (MDB).
Myodural Bridge
The suboccipital triangle is a group of muscles located at the base of skull on each side of the head. These muscles form a pyramidal shape and bony attachments to the atlas (C1) and axis (C2). The contents of the triangle include a section of the vertebral artery, suboccipital venous plexuses, and the first cervical nerve, C1. The main functions of this group of muscles are postural support, extension of the neck/head, rotation of the neck/head, and positional awareness, also called proprioception.
The dura mater is the outermost layer of the meninges for support, protection, and stability of the spinal cord. This layer of the meninges is densely populated with nociceptors, our body’s pain receptor, making it very sensitive to the sensation of pain.
How does MDB cause headaches?
Normally, active and passive contraction of suboccipital muscles puts the myodural bridge under tension, therefore transmitting forces across it to tense the dura and stabilize the spinal cord to resist dural infolding, inhibiting the pain mechanism.
However, if there is cervical spine joint dysfunction or the suboccipital muscles are too tight, abnormal tension is transmitted to the dura mater and clinical manifestations such as headaches are present. If trauma such as whiplash or concussion occurs, the suboccipital muscles begin to atrophy. When the muscles atrophy, their function is compromised and the dura mater is no longer supported properly, causing chronic headaches.
What are the common symptoms of MDB headaches?
Trigger Point Referral of the Suboccipital Muscles
- Unilateral throbbing pain located at the base of the head that radiates into the temple areas and possibly behind the eyes.
- Headaches that last anywhere from several minutes to several days.
- Tenderness to touch at the base of the head
- Made worse by head and neck movement
- Neck pain may or may not be associated
How can chiropractic care help me feel better?
Spinal Manipulation
Cervical and thoracic spine manipulation and releasing of the suboccipital muscles assist in relieving the excess tension of the myodural bridge on the dura mater, therefore alleviating pain. Studies have shown that manipulation of the cervical and upper thoracic spine reduces headache intensity, frequency, and duration of headaches after each visit.
Soft tissue intervention
Manual myofascial therapies targeted to the suboccipital muscles and the tight muscles surrounding them reduce excessive tension on the dura mater and promotes relaxation. Therapies include post-isometric relaxation (PIR), trigger point therapy, and instrument assisted soft tissue mobilization (Graston®).
Therapeutic Exercise
Progressive postural awareness exercises to improve proprioceptive awareness and muscle imbalances. Postural kinesiology taping can assist in retraining of the muscles in the cervical and thoracic spine.
We are ready to help you feel better. If you have questions or think you suffer from this type of headache, make an appointment to see us! Call us at 207-866-7000.
References:
Hack GD, Koritzer RT, Robinson WL, Hallgren RC, Greenman PE. Anatomic relation between the rectus capitis posterior minor muscle and the dura mater. Spine. 1995. 1;20(23):2484-6.
Enix DE, Scali F, Pontell ME. The cervical myodural bridge, a review of literature and clinical implications. The Journal of the Canadian Chiropractic Association. 2014;58(2):184-192.
Page P. CERVICOGENIC HEADACHES: AN EVIDENCE-LED APPROACH TO CLINICAL MANAGEMENT. International Journal of Sports Physical Therapy. 2011;6(3):254-266.
Dunning JR, Butts R, Mourad F, et al. Upper cervical and upper thoracic manipulation versus mobilization and exercise in patients with cervicogenic headache: a multi-center randomized clinical trial. BMC Musculoskeletal Disorders. 2016;17:64. doi:10.1186/s12891-016-0912-3.
Garcia JD, Arnold S, Tetley K, Voight K, Frank RA. Mobilization and Manipulation of the Cervical Spine in Patients with Cervicogenic Headache: Any Scientific Evidence? Frontiers in Neurology. 2016;7:40. doi:10.3389/fneur.2016.00040.
Scali F, Marsili ES, Pontell ME. Anatomical connection between the rectus capitis posterior major and the dura mater. Spine. 2011;1;36(25):E1614-4. doi: 10.1097/BRS.0b013e31821129df.
Fakhran S, Qu C, Alhilali LM. Effect of the Suboccipital Musculature on Symptom Severity and Recovery after Mild Traumatic Brain Injury. American Journal of Neuroradiology. 2016; 1-5. DOI: https://doi.org/10.3174/ajnr.A4730
Alix, Matthew E. et al. A proposed etiology of cervicogenic headache: The neurophysiologic basis and anatomic relationship between the dura mater and the rectus posterior capitis minor muscle. Journal of Manipulative & Physiological Therapeutics. 1999;22(8):534-539. http://www.jmptonline.org/article/S0161-4754(99)70006-0/fulltext. Accessed May 2017.
Headache Disorders fact sheet. WHO.int. http://www.who.int/mediacentre/factsheets/fs277/en/. Published April 2016. Accessed May 2017.
Cervicogenic Headache. Physio-pedia.com. http://www.physio-pedia.com/Cervicogenic_Headache. Published unkown. Accessed May 2017.
Photo Credits:
Myodural Bridge: http://uk.touchpoint.dk/news.asp?ID=26985
Suboccipital Muscles: http://www.synergyspokane.com/pain-symptoms/head/headache-patients-getting-better/
Trigger Point Referral: http://uk.touchpoint.dk/news.asp?ID=26985